Automatic fuel-feeding device.



A. R. SELDEN. AUTOMATIC FUEL FEEDING DEVICE.

APPLICATION FILED D120. 18, 1908.

Patented Feb. 28, 1911.

4 BHEETBBHEBT 1.

INVENTOR:

WITNESSES:

T A. 3. SELDEN. AUTOMATIQ FUEL FEEDING DEVICE.

APPLIUATION FILED 1120.18,;903.

Patented Feb. 28; '1911.

4 SHEBTB-BHEET 2.

T INVENTOR:

. e w|\\|\|A m w I I! "1 J H D X k m MIN H E k m n In. S vm mm mm mm v Q g J v N e i R f e n S e \w f m. :v 1/ Wk v mm H r 1 I um Nw aw M mm 3 ou X 1 \W hi lnu H l 1150 E m V E I I M um mh & v B Y R \i mm 2 NS E a. u mmwmv m m 2 my 3 e R 2 m9 S e .m e 5 2 2: mm m e N2 e z E m h mu a. H e mu. n .mo\ mdE N 0 WITNESSES:

f fi e A. R. SELDEN.

AUTOMATIC FUEL FEEDING DEVICE, APPLIUATION IILEI) 1030.18, 1908.

985,21 1 Patentd Feb. 28,1911.

4 SHEETS-BHBBT 3.

FIGS. F|G.4.

WITNESSES: INVENTORY:

ARTHUR it. SELDEN, or noonnsrna, new YORK, ASSIGNOR or ONE-THIRD T WILLlAhI 11. CALDWELL nivn ONE-THIRD To 0. SCHUYLER DAVIS, BOTH or ROCHESTEB,-NEW

, YORK.

To all whom it concm:

a citizen, of'th'e United States, and resident ofRochester, in the county of Monroe and 1 State of New York, have inventedfcertain new and useful Improvements'in- Automatic Fuel-Feeding Devices, of which the following is a speclfication.

This' invention relates to automatic fuel feedin devices, and its principal object is to pr uce a machine that is adapted to han dle commercial grades of coal, and that will utilize to the best advantage in the processes o-fcombustion the air or-steain by which and with which the fuel is fed to the furnace."

Other advantages will be'disclosed in the course of the specification.

In the drawingsz-Figure 1is a side elevation of a machine embodying the present invention; Figs. 2 and 3 are, respectively, sections on the line 2-2 and 3+3 of Fig. 1; Fig. 4-13. a section on the line 14 of Fig. 2; Fig. 5 is a cross-section on the line 5-5 of Fig. 4:; Fig.16 is a cross'section on the. line 6 6 ofFig. 4; Fig. 7 is an exterior elevationaof the parts shown in Fig. 4t; Fig. 8 is an elevation of the feed pipe from'the side "opposite to that shown in Fig. Fig. 9 is i a crosssection on the line 9- 9 of Fig. 8;

' Fig. 11 is an enlarged cross-section on the Fig. 10 is an enlarged elevation of a detail;

line 11 -11 of Fig. 9; Fig. 12 is an enlarged front elevation of a portion of the actuating mechanism; and Fig. 13-is a side'elevationthereof.

The improvements in question are shown n connect on with a stoker that is mounted upon ti -carriage .1 in order that itmay bewheeled'into place before the furnace door,

when it is to be used, and as readily removed when occasion may require. To this end the forward legs 2, 2 of the carriage areset on wheels 3,8, respectively, and the legs at, t at the rear, which normally rest upon the floor, can be elevated till they are free from the floor by a two-wheeled truck 5. This truck carries a projection 6 that slips into a socket '7 centrally "located on the frame (see Figs. 1, 2 and 3), and takes the load at the rear of the carriage when said projection 6 is raised into a vertical position by the handle-bars 8 of the truck.

The stoker comprises the following elements, all of, which, may besupported upon the carriage, and are so shown, viz: a hop casing 10 that contains the 'spring 23 placed The AUTOMATIC roar-FE DIN nnvron.

which the fuel isdischarged into the fun. nace; a conveyer by which the fuel is car ried from the hopper to the feed-pipe at a uniform rate; crushing means located be H UNI when I 1 Specificationof Letters Patent; Patented Feb 28, 1911 application mea-nehemberis, 190s, Serial No. 468,220, l

penfor the fu'elsupply; a feed pipe from Be it known that I, ARTHURR. .SELDEN,

tween the fuel conveyor and the feedJ pip'e;

a blower or other source of fluid pressure for discharging the fuel from the feed-pipe into the furnace a moving plate to spread the stream of air and fuel over the grates as it issues from the spout, or mouth of the feed-pipe, and an engine or motor operativel-y connected to those of said parts that are movable.

The screwcon'v eyer 9 (which is selected as being best adapted for a continuous, even feed, and which is most desirable), and the casing 10 that contains it, lie at the base of the hopper l1, and, extending forward beyond it, deliver the coal to the crushing rollers Hand 13. The screw-conveyer and its casing are supported at the rear by a supplemental frame 14, and forwardly by casings 15 and 16. The hopper is preferably long, from the back toward the front of the machine, and again preferably is open at the back for the reception ofthe coal. The

screw conveyer is open at the top from end to end, but between the hopper and the casting 15 (see Fig. 1) the upper half of the casing 10 is made in. the form of two lidlikeypieces 17 and 18 (see Fig. 6) that are hinged at 19 and 20, respectively, to the lower half of the casingnnd are locked together yieldingly by a latch 21 on one of them (18) that engages a shoulder 22 on the other (17 and is held normally against it by a compressible between an arm 24 carried by the latch and a seat 25 on the casin 10. lower ed e11 of thefront side 0 the hopper (see ig. 1) is some distance above the lids 17 and 18, and the intervening space is closed byflanges 17 and 18 on said lids,

respectively,

Q35 sufiiciently to permit the passage of anything dothe a .,b eneath the coal supply-in the-hop -it reaches the lower rear edges" of the 17 and' 18,;where the screw-conveyor brings; greater crushing pressure to bear upon; the

be crushed at this point in the .to discharge the unmanageable piece fromor to carry-it forinto the screw-conveyer,'and s not vcrushe by the latter against the sidejof th it will .be'ca'rried forward bylth conveyor along the edge Of -its as undesirable piece than it can Where the edge" of the casing receives lngly, the screw-conveyer and the edges ,ef

the thrust. Accordthese lids 17 and 18. are sufiiciently substa tial to crush any piece of coal that can b e-; while pieces of, foreign substance that arrive there, toolarge come caught between them to pass through the casing and too hard to manner aforesaid, will release and. open the lids 17 and' 18, thereby relieving the strain upon the machlne, and enabling the screw-conveyor either the machine altogether, ward and deliver it-to the. crushing rollers 12 and 13. i

The spring 23 by which the is e on trolled is sufiiciently strong'to resist such pressure .on the lids '17 and 18 as'may be re-' quired tocrushpieces of coal, but when anything harder is caught at this pointit yields before the safety'lofthe machine is threatens ,The lidsextend forward into under ordinary conditions,

the recess 26 (see Fig. 4), and arethus'pre- 1 vented from. opening unnecessarily wide, for

they engage the casing 15 after having opened are important features of it, and are among those for which protection is sought.

When coal is injected into thefurnace, it can be distributed best when it is approximatelyuniform in size, for then it will all have aboutthe same, momentum when it en"- teIfs thegfurnace, Furthermore, experiment has established that for-general purposes and other things beingequal, the best fire can be obtained when the pieces are comparatively small -probably within an inch where bituminous coal is problem then is to reduce concerned. 7 This the? coal to comparatively uniform size, without too great cost, and without employing means that will impair the regularity and uniformity of the feed, for stokers of this kind'are designed for aneven, uniform feed that will prac- .tically replace the coal as it. burns on the grates and maintain a thin bed. But to crush the coal before using it is so expensive that it is prohibitive in the case of small plants while to put a crusher; within the hopper in place of thescrew-conveycr, as has been done, is to sacrifice the uniformity and regularity that is so important, as stated,-

piece gets part in their longest diameter.

.- intthe: operation of feeding the coal to the And, finally, to place the crusher hopper, above the screw-convey'er Iin'ejces'sarily heavy 3 load upon nyjit is obliged to work in and sadvantages that need not. be disn detail. But when a crusher (as, ,p j that comprising the spaced r512 and 13) is placed beneath the, de-

, ,livery end of the screwconveyer, as shown -n ,the odrawings (see Fig. 4), and is so'adpipe,then the crusher is required to handle .onlyxa small proportion of the .coal that passes through it (fora large proportion of the finer commercial grades of: bituminous coal that are sold on the market is finer than the maximum size that will quired forthe furnace), are operatednpon by the crusher will not disturb the uniform character of the feed. The rollersare shown with their axes at usually be rerightangles to the hub 28 of the screw-conveyer because in that matter to'gear them (or'motor), thoughit results in a more compact construction to place them parallel with, and on eachside of, the casing of the screwconveyer, and that also brings the Hopperv somewhat lower down. 7 The crushing rollers are adjustable with respect toeach other for spacing, and furthermor'e one is adapted to give- Way, in order to save-the machine, whenanyt-hing too hard to crush is caught'between them. To this end the shaft 29 of one of the rollf: ersf (12) is journaled in the the-shaft 30 of the other roller naled' at each end in a block 31 (see Fig.7) that is movable in the casing 16, transversely to the shaft of theroller. The rear end of the casting 16 is closed by. a removable plate 33 secured byscrew's 32 (see Fig.4); Springs 34, 34 between the blocks 31, 31 and the ends of the plate 33 (see Fig. keep the roller position it isa simple (13) v is jour- 35,. 35 in the casing 16 permit the roller to move transversely for adjustment, and also that is too hard to be crushed. Access is also given to the space above the rollers'to remove foreign substances through a hand hole36f(see Fig. 4), that is closed by a plate hole mass-.of-coal), and has 3 existed-that coal within the maximum size desired' dropsjfreely through it into the feedand the pieces that to thedrivingengine l casting 16, while .13 normally in the desired position, and slots 15 whenever anything is engaged by the rollers 37 held in place screws 38, 38 (see Fig.5)

Since comparatively few of the piecesof coal that fall from the screw-conveyor will require crushing, very'little power isrequired for the operation of the rollers;

It has been found in practice that the coal is apt to become wired in its passage through the screw-conveyer, particularly when wet and fine. The rollers disintegrate it, and if they fail to do so before the pocket above them fills, then the screwoperates upon the mass to force it down upon the rollers, and so through them. Thus clogging is impossible. The inner surface 39 of the casmg is curved as shown in Fig.4: to direct" the coal to the rollers. i

The location, between the feed pipe from ur n'ace,- and the screw-eonve'yer' whereby it isqfcon veyed frorn'the fuel supply to said feed-pipe which fuel is'discharged into the" at a uniform rate, of a" crusher'thatfis adapted to reducethe coal'to the size desired without impeding the uniformity ofthe said feeding operation, is. one of the important features of the invention for-"which protection is sought.

1 A"blower'-tl-1' (see Fig. 1). is shown as the means for furnishing a fluid pressure to ex- 'Figs. 1 to 4:, inclusive,

pel the coal from the spout or mouth of the feed-pipe 27. In the construction-shown in which the coal falls from the rollers, hasa fiat surface 42, while its upper part -43 ,lS

curved to fitwithin an outer pipe 4:4: (see Fig. 1)

that is attached directly to the blower. The feed pipe 27 is supported wholly at its rear end where it lies on a crossrod 27 (spe Figs. 1, 7 and 8) that is fastened in the casing 16. Said feed-pipe is openat its outer end, through: which it receives air from the blower. I An adjustable damper (see Fig. op-

.erated by .a suitable lever.45 (see Fig. 8)

regulates the proportions lD-Wl'llCl] the air is delivered from the blower above'and below the'bottom 42 of the feed-pipe,respectively, when the second passage is'mad'e use of for purposes that presently will be described. In the drawings the second passage is represented as formed by a rotary sleeve 46 that joins the outer pipe 44, thus entirely inclosing the feedpipe 27, which extends through said, pipe ltto, or near, its outer.

' end, as indicatedbydottedlines in Fig. 1.

If the lower passage is omitted, the full vol-' ume of air from the, blower passes into the-v feed-pipe 27, as isfthe case when the damper 15 is in theclosed position shown. in Fig. 4c.

The rotary sleeve 46 has near each end, and integral with it, two annular ribs or collars 47, 47 (see Figs. land 8), that f'ormbetween them a runway thatis adapted to receive rollers 49. These rollers are rotatably the other end on brackets on 52 (see Fig. 5 The sleeve 46 is utilized to that passes over supported on rods 50 three of which are shown (see Fig. 2), all'of which are'fixed rigidly at one end in the fire-plate 51'and at rock. the fuel-spreading plate 53 back and forth, at angles with the vertical'plane, and to that end the sleeve is rocked by a chain 54;

end to the segment 55. The operation of the the feed-pipe 27, upon cross frame' plate it and is attached at each ent will be explained as part of the description of the mechanism that drives the movable parts. fuel-spreadingrplate 53 is also given an oscillatory movement at angles with the horizontal plane by an arm 54 (see Figs. land 8) that is operated by a link 55*, and thatin turn is connected with a ing plate 53. Accordinglyas the crank '61 rotates, it recipr'ocates the collar 58, and, by

reason of the connection between the collar 58 and the fuel-spreading plate 53 (through the roller 57,rod 56 and link 55*), causes in turn said plate to rock on its pivot 53*.- At

the same time that the fuel-spreading plate 53 is oscillated inwardly and outwardlyv in front of the spout, or mouth, of the feedpipe 27, from which thefuel is discharged into thefurnace, itv (said plate 53) is belng rocked transversely to and fib" by the rock ing of the sleeve'46, as before explained, so that the'fuel is spread on both sides of the grates, latter movement causes the roller 57 tofmove idly in the grooved collar 58 without disturbing the operative relation of these parts. The lower passage 63 beneath'the bottom 42 of the feed-pipeproper Q'Tis designed for a fluid pressure that may consist of air,

or steam or both, and which-is discharged as'well as from front to rear. This through thislower passage .63 in. order to atl cel'erate the course of, the fuel: through the feed-pipe 27, and also, if desired, to direct the course of the current of fuel and 'air' discharged from the spout or mouthof the feed-pipe. the lower passage and steam, if used,' enters through a forwardly-directed noa z'le'l68 that can conveniently be introduced into thepassage through the under partof the pipe 44. The air and steam are forced through the lowerpassage 63 under [To this end air is admitted t6 63 from'the blower 11 by the damper 45 (see Fig. a),

ressure. and are dischar ed throu 'ha vent or passage 65' left between a plate 64 that closes the end of the passage GSandt-he end: 67 ofthe floor 4.2 of the feed-pipe 27. Th e discharge of air or steam at this point ,both

throws the fuel up against the spreading zle. Other vents o-r passages 66 may be provided that are represented as cut transvei'sely across the bottom 42 0f the feed-pipe different points throughout its length (see dotted lines I steam discharged through these vents 66 in Fig. 1), and the air or 53, and assists the air-current in the .feedpi'peby sucking the fuel frornthe nor mix steam with the, fuel dischargedinto the furnace from the spout of the feed-pipe, and

. vpipe.

I steam through the ventG5 are'provided ,Ifa downwardly-directed, oscillating spout 'or no-zzle s used upon stolzersadapted for V such a flame burns holes in the fire-bed, and

and throwing the fuel into the upper part of protected, respectively, by overhanging forweirdly-directed lips 66 bent up from the for feedingflpulverized fuel, where the observes to accelerate the fuel in its-passage through the feed-pipe, preventing clogging the feed-pipe where the air-current v is s'trongestifl he vents 66 are represented as bottom 42 of the feed-pipe, which also diroot the air or steam forwardly toward the spoutor mouth of the feed-pipe. The lower passage 63 is useful when it is desirable to when fuel is being fed in such quantities that there is danger of its clogging the feed Other means besides the discharge of air for. 'di.recting-- toward the fuel-spreading .plate the "current of fuel and air discharged froni the spout or-mouth f the feedrpipe 27 by slanting upwardly the feedpipe 27, or, if preferred, the outer endflo f the, bottom 42, as shown by dotted lines in Fig.1. .This stoker .is.to be distinguished fronrthat class ofstokers that are designed je'ct s to'form an inflammable mixtureof the'airand fine 13311161 85 ofv coahand soto since the fuel is not placed by the deflector,

ates in a different manner.

discharge it into the furnace, that it: will burn-at the spout or nozzle of the-fecd-pipe.

pulverized fuel, and pulverizeldffuel is used the flame produced .by the fuel burning. in suspension at the mouth of the spout, to gether with the -surplus-' air discharged fronr it, has la-blow pipe area upon whatever coal may have escapedignition and fallen 'upon the grates, which produces clinkers; that it fuses into theigrates. At the same time.

injures other parts the furnace besides the grates. On the other hand, ifanoscillatingf spout or nozzle is used with coarser fuel that for the most part mustbe burned upon the grates,-it focuses the airdischarged from the spout sothat it tends to extinguish the fire wherever it strikes, while none of, the otherparts of the combustion chamber receive; sufficient air from this source. The

the casting Stoker heredescribed on the other hand is I intended for coal. of cominercialgrades, and g is adapted for bituminous slack, semi-bituminous, andfine anthracite, so that the mam ,1 considerations here are, first, to lay the coal .evenly upon the grateswithout introducing an excess of a1r, by a continuous stream that replenishes the coal as fast as it s burned upfin order that a bed, of. uniform depth I shallbe maintained, and secondly, to spread the air discharged from the spout of the} feed-pipe as much as possible over the grate surface. Again, stationary deflectors, or thosehaving a vertical oscillatory move= in opposite directions.

ment only, depend for the even distribution of the coal upon its rebounding from the deflector, and upon the law of general average, upon the grates or definitely guided thereby. The spreader of The larger pieces may'rebound from it when it is interposeddirectly in the path of the fuel as it issues fromthe spout of the feed-pipe, but

the present invention opera as the spreaderturns this Way and that it positively and accurately discharges the coal over difi'erent parts of the grate, covering all parts uniformly. By slanting up the end 67 of the bottom 42 of the feed-pipe 27, as shown in dotted linesin Fig. 1, or by employing a draft up through the :vent 65. at

this point, the tendency 'of the coal to re-- bound from. the spreader 5.3 is minimized, for then it isthrown up against the under side of the spreader-as it issues from the contour ofthe spreader, to bedischarged in a stream from its forward:edge.v This is also of import-mice as it controls Whatever dustv may be in the fuel. Ordinarily. the dust is blown over the bridge-Wall when'the spreader isin its elevated positions, but if blown up against the under side of the.

spreader, it is definitely directed down into the I i the air as it, issuesfromthespoutofthe feed-pipe 27, expands as. soon as it enters the furnace, and its forwa rd impulse whioh tcndsto cause it,,to'streainfdirectly across spout of the feed-pipe 27, and follows the flames and is consumed at once. F inally,

the furnace}andfover the bridge wall, is -here' utilized the'fspreader 53 tosend itinall di recti ons over the fire. Thelmorfing tuated. by a prime mover 68 (in the drawpartsl' of the machine are aci s: a steam engine) mountedlon the top of opposite side drives all the 7. other movable parts. The belt 70 leads over a' pulley 71 on the countershaft a bevel gear '18 on the end opposite the crank 61, which meshes withanother gear .79 that is journaled in a part 80 of the frame. 0a

the end of the short shaft that carries the last mentioned gear a crank 81 is fixed (see Fig. 3), and a pitman 82, pivoted in its end,

v 72. A pinion. 73 on this. shaft, (see Figs. 1 and 13) meshes with a I A belt 69 on one side of it drives the blower 4:1, and a belt 70 .on the upon the rock-shaft 8 1, carries the segment 55.

and that, in turn, As the gear 74 rotates continuously, the crank 81 is also roscribed.

down, thereby rocking 13, and is asfollows: The "conveyer shaft 28 swinging 1 has fixedto it" a bevel gear 86, that meshes ''with a similar gear 87 The latter is fixed upon one end of a shaft 88 that is supported ina bearing 89, while a ratchet wheel 90 is loose uponthe other end of saidshaft. Betweenthe wheel 90 and the bearing 89 is a i a ityfrom; being compressed. If, however, a

jpiece-o'funbreakablematerial is caught in either the screw 9 or the crusher rolls 12 andupper end collar 91+that-als'o is fixed to the shaft 88, and on said collar is a projecting lug 92. A lever 9.3 is pivoted on the wheel 90, and'enagesat its short end 93 with the lug 92 z 1g. "13). The long arm of said lever rests on a spring 94 that is carried on the wheel 90. As the latter is rotated in the direction" indicated, they lug 92 is caught by the end 93 of the lever 98', and the collar 91, the shaft 88, 'andthe gear 87 are rotated thereby, I The resistance of the spring 91to the force exerted-in this motion is suflicient to prevent 13, the resistance becomes so great that'the lug 92'causes the "long end of the lever to swing downward, compressingthe spring 94, and releasing the end 98 of the lever from said lug. The wheel 90 continues to the obstruction and until the lever 93 again. catehes'the lug 92.

The wheel 90 1s rotatedby suitablemeans,

so 'as to be; easily regulated to diiferent speeds. A "'COI1V6I118I1t driving and regulating mechanism'is shown in Fig. 1f. 3 A rocker arm 95-'is"pivoted on the carriage 1 at 96, and carries a cross-head 97 that is movable to any. point upon the arm by means of a screw-threaded spindle 98. Said cross-head is connected with a pitman 99 that is pivoted on the gear 75 at 100. Pivoted tothe of the rocker-arm 95 is a pair of rods 101, 102, provided at their free ends with pins 108 engaging the ratchet wheel 90. The said pins are maintained in engagement with the teeth of said wheel by a spring 104: that pulls the rods 101, 102 toward each other. As the pitman 99 is moved back and forth bythe rotation of the gear7 5, the arm 95 is rocked back and forth,

connects it withan arm 83, that is fixed tinuous for operating the screwthe hub of thiis turning the conveyer-screw. 9.

'sentedby 68 in the drawings, a fiexible'couand the rods 101 and 102 are moved correspondingly. As said rods e gage opposite sides of the wheel 90, it foll s that the rod .101 operates said wheel only on the backward stroke, and the rod 102 on you the forward stroke. And since practically no time is lost between the forward and backward strokes, the screw 9 is rotated with practically a conmovement. The adjustment of speed is easily eifected by raising or lowering the cross-head 97 on the arm' 95 by means of the spindle 98. Raising said cross head reduces the speed by shortening the movement of the rods 101,102, and lowering it increases the speed by lengthening the movement of said arm. In order to prevent per 11 from becoming bridged over the feed-. screw 9, as sometimes happens when the coal is both wet and fine, an'agitator orstirthe fuel in the .hop- I l ring device may be employed. In the drawings (Figs 1 and 3) a device for this purpose is shown that consists of a thin wheel .105, that is pivoted in the side of the hop.-

per and lies flat against'it. Said wheel haslarge teeth 10? around its periphery, that are of the proper pitch to be engaged by the convolutions of the screw 9. As the latter v rotates, it turns the wheel 105 and loosens the fuel along the side of the hopper, thus breaking any arch that 'theco'al may'have formed over the screw-conveyer.

..When a steam engine is used, as reprepling 108 gives it steam from the boiler, and the "exhaust steam is led from its exhaust port 109, either to the nozz1e'63, shown 'in Fig. has projecting into. the passage 63 for the purposes described above, or to the discharge pipe 110, beneath the grates, where thisstea-m'is utilized both to accelerate the draft throu h the grates, and to cool them.

Wheel c aim is.:-

tion of aafuel-hopper, a crusher adapted for easing connecting thehopper and the 'fjcrusher, a screw-conveyer inclosed within and closely fitting saidlcasing and adapted to transfer.'fuel under pressure from the hopperto andithrough the crusher, means rotate,.but the screw 9 stops until freed from 1. I ':"a mechanical stoker, the coinbinathe freepa'ssage of particles of fuel of less than a predetermined diameter, a fuel-tight fuel under pressure from the hopper to and through the crusher, means for rotating the screw-conveyor at a constant speed to roduce a constant and substantially unif drm feed of fuel, and means for transferring the fuel constantly, as it is delivered from the crusher,'into a furnace.

3. In a mechanical stoker, the combination of a fuel-hopper, a crusher adapted for the free passage of particles of fuel of less an a predetermined diameter, a fuel-tight g connecting the crusher and the hopscreW-conveyer mounted within "and y tting the casing andada-ptcd to feed fuel to th crusher under pressure, means for rotating t screw-conveyer at a constant speed to prduce a constant and substantially .unifor feed of fuel through the crusher, a fee discharged fro the crusher, the feed-pipe being adapted o discharge the fuel into a furnace, and leans for supplying a constant bl id to and through the feed-pipe to convey the fuel constantly into the furnace as it is fed through the crusher.

4. In a mechanical stoker, the combination of a fuel-hopper, a crusher adapted for the free passage of particles of fuel of less than a predetermined diameter, a fuel and fluid-tight casing connecting the crusher .and the hopper, a screw conveyer mounted Within and closely fitting ,th'e casing and adapted to feed fuel to the crusher under pressure, means for rotating the screW-conveyer at a constant speed to produce a constant and substantially uniform feed of fuel through the crusher, a feed-pipe into which the fuelis discharged from the crusher, the reed-pipe being adapted to discharge the fuel into a furnace, and means for supplying a constant blast of fluid to and through the feed-pipe to convey the fuel constantly into the furnace as it is fed through the crusher.

tion Witha hopper for a fuel supply, of a screw located in 1ts throat; and a fuel-agitat- -pipe into which the fuel is 5. In a mechanical Stoker, the combinaing wheel having peripheral teeth, pivoted to the side of the hopper, and adapted to be operatively engaged by the screw-Iconi'eye'r; substantially as shown and described.

6. Ina mechanical stoker, thevcombination with a fuel supply, of a spout adapted to discharge the fuel into a furnace; means for conveying fuel from said supply to said spout; means for discharging the fuel from,

fuel into a furnace; means for conveying fuel to the feed-pipe; a passage for fluid under pressure communicating, with the feed-pipe at one or more points between the point where fuel enters the feed-pipeand the mouth of said pipe; meansfor supply ing a fluid under pressure to both said feedpipe and said passage, whereby the fuel is discharged into thefurnace; means for regulating the proportionsin which the fluid is delivered to said passage and feed-pipe, respectively; and a deflector located beyond the mouth of the feed-pipe in position-to receive-the fuel discharged therethrough substantially as shown and described.

8. In a mechanical stoker, the combination of a fuel crusher having a passage t-herethrough of fixed normaldiameter, and adapted tocrush pieces of fuel of greater diameter than said passage, means for forcing a constant and uniform stream of fuel under pressure through. the crusher and means for discharging the fuel constantly 'into' a furnace as it issues from the crushen ARTHUR R. SELDEN. 

